Toy air car



Dec. 20, 1966 Filed Oct. 2, 1963 F. A. DOBSON TOY AIR CAR 5 Sheets-Sheet1 IN VEN TOR @fl/r/A z/A/ ,4 502mm F. A. DOBSON Dec. 20, 1966 TOY AIRCAR 5 Sheets-Sheet 2 Filed Oct. 2, 1963 INVENTOR. @AA/A l/A/ A 50550Dec. 20, 1966 F. A. DOBSON 3,292,721

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Dec. 20, 1966 F. A. DOBSON 3,292,721

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United States Patent M 3,22,721 TOY AIR CAR Franklin A. Dobson, 4518Roxbury Road, Corona del Mar, Calif. 92525 Filed Oct. 2, 1963, Ser. No.313,388 16 Claims. (Cl. 180-7) My invention relates to an improvedair-cushion vehicle and particularly to a very light weight, low powervehicle in the toy vehicle category. By toy is meant that class ofvehicles which can be used by both adults and children, but primarilyfor pleasure use and as a leisure time activity. Another example of sucha toy vehicle is the well-known four wheel kart or go-kart.

Machines of the air cushion variety known presently in the art as aircushion, ground cushion or ground effect machines, include an airpressure chamber open to the ground plane. Air pumped into this chamberleaks out around its bottom edges and the increased pressure inside ofthe chamber lifts the vehicle slightly above the ground plane. After thevehicle is raised above the ground, only a small propulsive force isrequired to move the vehicle over the ground surface, since the cushionof air provides a very low frictional support. Such air cushion vehiclescan be used over such diverse ground plane surfaces as land, fields,grass, swamps, beaches, water, and snow.

The air cushion principle furnishes an efiective method for creating alarge liftfor a relatively small expenditure of power. For a givenlifting area, the power required varies directly with the distance fromthe ground, and with the three-halves power of the total weight liftedper unit area.

For a given application, the available lifting area is generally limitedby the maximum size of the vehicle which can be used. It thereforebecomes of the utmost importance to keep the structural weight of thevehicle to a minimum. A significant teaching of my invention is how toconstruct in a very simple manner an air cushion vehicle which meetsthis requirement,

Another object of my invention is to provide a very efiicient blowersystem for an air cushion vehicle.

My invention further describes and illustrate an improved means forenabling air cushion vehicles to clear obstructions which are higherthan the clear height of the vehicle above the ground plane.

A major source of difiiculty with existing air cushion machines has beenthe difficulty of achieving adequate control without the expenditure ofexcessive amounts of power. This problem has also been solved in asimple manner in my invention.

Other and further objects, features and advantages of the invention willbecome apparent as the description proceeds.

Briefly, in accordance with a preferred form of the present invention,there is provided an air cushion vehicle having a light weight bodyformed by a light, rigid framework covered with a thin shroud ofmembrane. An inner cockpit within the body has an opening for theoperator through the body top. The cockpit is streamlined with bothsides converging at the front and rear ends, thereby serving to separatethe two sides of the 'body and act as a splitter for the air flow fromthe intake fan.

Substantially the entire front end of the vehicle body is occupied by anair intake in which a motor driven fan is mounted in a sloping position.As described below, this location of the fan intake produces a sideforce when the machine is flying at an angle of yaw, this side forceallowing the vehicle to be maneuvered in a comparatively short turningradiu without excessive Patented Dec. 20, 1966 side slip. Directionalcontrol, propulsion and braking are provided by flaps forming a portionof the upper rear right and left surfaces of the 'body. These flaps arepivotally mounted at their rear edges upon generally horizontal axes andare adapted to move in both the same and respectively oppositedirections. When the flaps are moved into the body, a forward propulsiveforce is produced; contrariwise, when the flaps are moved out of thebody, a braking propulsive force is achieved. The yaw control isobtained by differential movement of the flaps. Details of these andother features including a flexible skirt for increasing the effectiveground clearance of the vehicle are described in the following detaileddescription taken in connection with the accompanying drawings in which:

FIG. 1 is a perspective view of an air cushion vehicle constructed inaccordance with my invention;

FIG. 2 is a plan view of the air cushion vehicle of FIG. 1;

FIG. 3 is an elevation view of the air cushion vehicle with the shroudcovering removed;

FIG. 4 is a sectional view taken along line 44 of FIG. 1;

FIGS. 5(a), (b) and (c) are perspective views of the control flaps inrespective propulsion, braking and directional control positions;

FIG. 6 is a schematic diagram illustrating the improved directionalcontrol afforded by air cushion vehicles constructed in accordance withmy invention;

FIG. 7 is an elevation view of an alternative embodiment of my inventionhaving an improved'flexible skirt for increasing the effective groundclearance of the air cushion vehicle;

FIG. 8 is a cross-sectional view taken along line 88 1 of FIG. 7;

FIG. 9 is a perspective view of an alternative embodiment adapted forlanding on the water; and

FIGS. 10 and 11 are respective plan and elevation views illustrating thephysical variables of the skirt and flap structures shown in FIGS. 7 and8,

Referring now to FIGS. 1, 2 and 3, a streamlined body 10 is formed by alight weight rigid framework 11 and a thin covering flexible shroud ormembrane 12. The framework includes two arcuate bottom side members 13,14; horizontal bottom cross members 15, 16, 17 (FIG. 2); a rear crossmember or frame 18; and frontal bottom diagonal supports 19, 19'. Theseframe members, for example, may be formed of by .028 inch chrome-molytubing. A streamlined cockpit 25 is supported upon the horizontal framemembers 16,

Cockpit 25 includes respective side members 26, 27 which converge at thefront and rear ends thereof. These sides taper vertically from the frontof the cockpit toward the rear. The cockpit further includes acontinuous floor 28 and an upper deck 29 having an opening 30 for theoperator cut therein. The side and upper deck panels may be formed, forexample, of /8 inch plywood and the floor of inch plywood. Front andrear bulkheads 31, 32 (FIG. 3) formed of /2 inch pine or spruce, forexample, complete the cockpit. Other light weight materials such asaluminum or laminated fiberglass may also be employed for forming thecockpit 25.

The streamlined cockpit 25 serves the purposes of supporting theoperator and housing the controls described below. Additionally, thecockpit acts as a splitter to the airflow produced by the fan, alsodescribed below. This configuration offers excellent lateral stabilityfor the reason that the two separated sides tend to act independently ofone another. Thus, as either side ap- 3 proaches the ground, its lift isincreased, causing a righting moment.

Two skids 35, 36 are attached to the lower sides of the respectivelongitudinal frame members 13, 14 by bolts 37, and provide a bearingsurface when the vehicle is resting on the ground.

A cylindrical ring 40'having a diameter of the order of the frontalwidth of the vehicle is supported in a sloping position between thehorizontal frame member 15 and the upper portion of the cockpit body 25.

The shroud 12 and the structure to which it is attached are so designedthat the shape of the shroud is maintained by the internal air pressure.Therefore, the shroud may be made either of flexible material or a verylight rigid material. The shroud is supported when not internallypressurized by a light internal framework comprising, as shown in FIGS.2 and 3, arcuately shaped body frame members 41, 41, 42, 42', 43,43fastened from the bottom side members 13, 14 to the edges of cockpitsides 26, 27. This framework is completed by longitudinal members 44, 45and 46 spanning the open sides.

Shroud member 12 preferably comprises a thin vinyl or other plasticmaterial with reinforcing fibers for added strength and having athickness of the order of .005 inch. As shown in FIG. 4, this coveringis easily aflixed to the framework by double face adhesive tape 50applied between the tubing members and the interior face of the plasticsheet material. As shown in FIG. 1, there is thus formed a body having ahollow underside providing a substantially air-tight air pressurechamber and having an air intake 51 formed by the cylindrical ring 40.

A motor driven fan assembly is mounted in a sloping position withrespect to the ground surface in the air intake 51 by an invertedY-shaped motor support 55 spanning the ring 40. Engine 56 supportedthereon drives a propeller 57 aflixed to shaft 58 which has respectiveends rotatably mounted in bearings 59, 60. Bearing 59 is affixed to thesupport 55 and bearing 60 is aflixed between the bottom of the frame 11and the front of the cockpit 25 (FIG. 3). Power from the engine to thepropeller may be transmitted by a chain drive comprising respectivesprockets on the engine and shaft 58. For low power vehicles, engine 56preferably comprises a karting type engine, a specific example being theModel 820L engine constructed by the West Bend Company of Hartford,Wisconsin. This engine is a two-cycle engine rated at 8 to 10horsepower.

A safety screen 65 is mounted in the exterior of the air inlet 51 and aplurality of radial straightening vanes 66 are mounted in the interiorthereof.

In a typical application, there are twelve tapered vanes 66 formed ofsheet metal, with the chord of the vane about equal to the spacing. Thesectionof the vanes is curved in a circular arc with the leading edgeparallel to the direction of air flow as it leaves the fan (about 30from the axial direction) and the trailing edges approximately parallelto the axial direction. These vanes remove the swirl from the air whichis passed through the fan 57, thereby increasing the efliciency of theblower system and counteracting the torque of the fan. The

efficiency of the blower system is further assisted by cylindrical ring40 which not only supports the engine and fan but also directs the airsmoothly into the air intake 51.

A relatively large stabilizing vertical surface 75 is attached to therear end of the vehicle (FIG. 1). A portion of this member forms arudder flap 77 hinged at 76 for contributing to directional control ofthe vehicle. Thus, by Well-known aerodynamic principles, a side forcecomponent is produced when the rudder is pivoted with respect to thevehicles'longitudinal axis. Movement of flap 77 is obtained bydepressing one or the other of the rudder pedals 78, 79 (FIGS. 2, 3).These pedals are hinged to the floor 28 of the cockpit and arerespectively connected to opposite sides of the rudder 77 by cables 80,81.

Movable flaps 90, 91 respectively form the upper rear right and leftsurface of the body 10. These flaps are respectively mounted along theirrear edges by generally horizontal pivot axes 92, 93 and provide meansfor propelling, braking and controlling the direction of travel of thevehicle. These flaps have a neutral position substantially flush withthe surface of the body '10 (FIG. .1) and respective lowered and raisedpositions as shown in FIGS. 5(a) and 5 (b). A preferred control meansfor these flaps comprises a control wheel 95 affixed to a shaft 96supported for both rotational and translatory motion in journal bearings97, 98 attached to the cockpit housing. An arm 99 is rigidly attached tothe forward end of the shaft and has respective cables 100, 101 attachedthereto. These cables respectively pass over fixed pulleys 102, 103 and102, 103 mounted within the vehicle body and the cable ends arerespectively affixed to the flaps 90, 91. The cables and 101 leave thearm 99 at angles of about 45 but in a plane parallel to the shaft 96.Forward propulsion is obtained by pushing the wheel.

95 forward, which causes both the flaps to be pulled down into the body10 against the pressure therewithin. AS. shown in FIG. 5(a), the escapeof air towards the rear. of

the vehicle provides a forward thrust.

When the wheel 95 is pulled back, a reverse thrust or braking force isproduced by air escaping in a forward 1 direction. As shown in FIG. 5(b), in this condition with vehicle.

Directional control is obtained by turning the wheel. 95 1 for producinga differential effect wherein one of the flaps is deflected into thebody 10 and the other of which isallowed to deflect out of the body asshown in FIG. 5 (c).

In this figure, the wheel has been turned to the right so. as to pullthe left flap 91 down, giving a thrust in the forward 'direction whilethe right flap has been allowed to deflect out of the body, giving athrust in the rearward direction. A side component force to the left isalso produced by the unporting of the outer end of the raised flap 90.Unporting of the inner end of the raised flap 90 which would produce aside component force to the right is prevented by the partial end plate105 or by a fixed end plate formed, for instance, by the vertical sideof cockpit 25. End plate 105 of flap 90 and end plate106 of flap 91vertically depend from the inner ends of the. respective flaps and blockthe flow of air at these flap ends when the flaps are in their raisedcondition. The forward thrust by the left flap and rearward and leftside forces produced by the right flap combine to give a turning momentin the right-hand direction for the flap posi.

tions illustrated in FIG. 5(c). A turning moment in the left-handdirection is obtained when the flaps are in the.

respectively opposite positions (when the wheel 95 is turned to theleft). Also, when the wheel 95 is pulled in fore or aft directions whilerotated, differential forces are still produced which combine to give aturning moment in the desired direction.

Additional directional control is obtained by appropriate deflection ofthe rudder pedals 78, 79. A particular feature of my invention is thatthe flaps 90, 91 extend proximate the rudder as shown at 110, 111. Someof the air escaping from the flap is deflected off the rudder andenhances the turning moment. Thus, in the illustra-.

tion shown in FIG. 5 (0) wherein a turning moment in the right-handdirection is desired, the right rudder pedal 79 may be depressed foradditional control whereupon air being exhausted from flap 91 willfollow the rudder 77 creating a suction on the left-hand side toincrease the right-hand turning moment. If desired, the rudder cablescan be connected to the control wheel 95 so that it is moved with theflaps.

The sloping position of the fan in the air cushion vehicle describedabove provides excellent visibility for the operator. Another desirablesafety feature of this fan position is that the occupants of the machineare not in its plane of rotation, A further advantage of the slopingposition is that it offers a simple structural arrangement wherein thebottom of the fan support is supported by the tubular framework and thetop by the cockpit housing.

Another significant feature of my invention is that the location of thefan intake at the front and facing forward produces a combination oflift and thrust thus increasing the efliciency of the vehicle. Also,because of the change in flow direction on entering the intake, a sideforce component is produced when the vehicle is moving at an angle ofyaw. This side force component, together with the side force acting onthe vertical tail 75, allows the vehicle to be maneuvered in a shortturning radius without excessive side-slip.

A further understanding of the excellent directional control obtained inair cushion vehicles constructed in accordance with my invention may beobtained by reference to FIGS. 6(a)6 (c). In FIG. 6(a) the vehicle isillustrated in normal straight-line flight with the relative Wind V inline with the center line of the vehicle.

FIG. 6(b) illustrates the vehicle when a turn to the left has beeninitiated by deflecting the rudder to the left as shown, by differentialmovement of the rear flaps, or by both. This applies a counterclockwisemoment to the vehicle, which causes it to begin to rotate in thecounterclockwise direction.

In FIG. 6(c) (a short time after the positon shown in FIG. 6(b)), thevehicle has now rotated an appreciable amount in the desired direction,and the rudder and flaps have been returned almost to neutral, with justenough deflection to preserve the desired rate of rotation. The relativewind V is now coming from the right of the vehicle, and when it entersthe fan intake it is forced to change direction to flow parallel to thevehicles centerline. At the point where direction change takes placethat is, at the fan intake-a side force A is produced which pushes thenose of the vehicle in the correct direction. At the rear of thevehicle, another side force B is produced by the wind acting on thevertical surface. These two forces, acting in the same direction, but onopposite sides of the center of gravity, push the vehicle laterallyaround a curved path, giving the desired turn.

These two side forces are obtained so long as the direction of flight isnonparallel to the centerline of the vehicle.

The production of a suitable side force is a signficant feature of thisinvention. Thus, representative prior art air cushion vehicles produceonly the side force B which, acting alone, has the principal effect ofspinning these vehicles about their center of gravity. For this reason,air cushion vehicles have the reputation of being substantiallyuncontrollable. For example, several large air cushion vehiclespresently being used require a turning radius of the order of half amile. Contrariwise, the present invention has a turning radius of theorder of 25 feet.

An additional embodiment of my invention shown in FIGS. 7 and 8 isdesigned to clear obstacles which are higher than the clear height whichcan be achieved between the bottom of the vehicle and the ground plane.Flexible skirts 125 depend from the right and left sides of the body.Flaps 127 and 131 are respectively hinged at the forward and rearwardends of the body 10. Respective ends of the skirts 125 are attached toends of the flaps 127, 131. The internal pressure caused by the fancauses the flexible skirt to assume a cylindrical shape (shown by dottedlines in FIG. 8) whose elements are normal to the plane of the curvedside members of the body frame 13, 14. The pressure is thus taken byhorizontal hoop tension stresses in the skirt, and the loads resultingat the ends are applied to the flaps. The flaps, however, are pushedoutwardly by the internal pressure within the flexible shroud 12. Theflaps may be retained in position by a spring (not shown) which urgesthe flaps to the position shown in FIG. 7. In a preferred embodiment,however, the skirts and flaps are proportioned to maintain stableequilibrium by the internal air pressure within body 10 so that theskirts and flaps automatically return to their original position afterbeing deflected on striking an obstacle.

The mathematical relationship determining flap and skirt equilibrium isderived as follows, in conjunction with the diagrams of FIGS. 10 and 11.In these figures, the front and rear flaps can be of different oridentical length, except that the front flap slopes inwardly and therear flap slopes outwardly. The total tension load L on a skirt of depthh for internal pressure p and radius of curvature r in a horizontalplane of the skirt is given by the equation This load may be consideredto act at one-half the depth of flaps and at the angle B from a normalto the flap hinge line. Therefore, the moment M of both skirt loads on agiven flap is M =2prh (cos B) /zh (2) As shown in FIG. 11, the width ofeach flap is h/cos A where A is the angle between the flap and thevertical, so that for an average flap length w, the total air load Lacting on one flap is given by the equation L =pwh/cos A (3) The momentarm of this load about the flap hinge line is one-half the flap whichwidth, so that the flap moment M resisting the skirt moment M is 7011) h2 MF 2 cos A) (4) For flap and skirt equilibrium, i.e. in order tomaintain the position shown in FIG. 7, moment M must equal moment M;giving the relationship W (COS A) 2r cos B (a) The system defined byEquation 5 is maintained stable by the internal air pressure. Thus,assume that either flap moves outward a small amount. The skirt is thenforced to straighten out slightly i.e. the radius of curvature of theflap must increase, which causes the skirt moment M to increase. Sincethe flap moment M is independent of flap angle A, the skirt moment isthen greater than the flap moment and the flap will return to itsoriginal position. Accordingly, the flexible skirts and movable flapsdefine the bottom periphery of the vehicle and have the effect ofincreasing the effective ground clearance of the vehicle, since they maybe deflected upwardly by obstacles without damage to the vehicle.

In an alternate arrangement (not shown) the forward flap 127 may beeliminated by carrying the body side member and skirt around the front.When this is done, it is advantageous to shape the flap pattern of theforward portion of the skirt so that it slopes toward the rear andallows it to pass over obstacles more easily.

When the skirts and flaps of FIGS. 7 and 8 are used, the skids 35, 36should be moved inboard and lowered enough so that the skirt and flapsdo not take the main load when resting on the ground. This structure isshown in FIG. 8 (35', 36). In an alternative embodiment, retractableWheels may be used, as also shown in FIG. 8.

An alternative embodiment of the air cushion vehicle as illustrated inFIG. 9 is adapted for landing on the water. Cylindrical floats 140 areattached to the longitudinal body frame members. Similar floats 141 maybe attached to the front and rear of the body and serve the additionalfunction of a protective bumper. The central cockpit 25 described abovealso assists in providing flotation.

Although exemplary embodiments of the invention have been disclosed anddiscussed, it will be understood that other applications of theinvention are possible and that the embodiments disclosed may besubjected to various changes, modifications and substitutions withoutnecessarily departing from the spirit of the invention.

I claim:

1. An air cushion vehicle comprising a lightweight body having a hollow,downwardly generally open underside for providing an air pressure plenumchamber;

an air intake occupying substantially the entire forward end of saidvehicle;

a motor-driven fan mounted in a sloping position in said air intake formaintaining air under pressure in said air pressure plenum chamber for(i) vertically lifting said vehicle, (ii) providing a horizontal thrustsubstantially parallel to the longitudinal axis of said vehicle, and(iii) providing a side force component at the 'front of the vehicle whensaid vehicle is flying at an angle of yaw;

a central cockpit extending longitudinally in said air pressure chamber,said cockpit having a sharp leading edge in the path of the air flowproduced by said fan so that the air pressure chamber is divided intotwo pressurized side-by-side cavities;

a vertical stabilizer mounted at the rear of said body, said stabilizercomprising a large vertical surface oriented generally parallel to thelength of the vehicle and extending away from said body, and

first and second movable flaps located in respective openings in saidair pressure plenum chamber on the left and right hand sides of the rearend of said body, said flaps being selectievly controlled from saidcentral cockpit for propelling, braking and controlling the direction oftravel of said vehicle.

2. An air cushion vehicle comprising lightweight body means having ahollow, downwardly generally open underside for providing an airpressure plenum chamber;

air intake means including an air intake and fan in the forward end ofsaid plenum chamber for (i) vertically lifting said vehicle, (ii)providing a horizontal thrust substantially parallel to the longitudinalaxis of said vehicle, and (iii) providing a side force component at thefront of the vehicle when said vehicle is flying at an angle of yaw;

central cockpit means extending longitudinally within said air pressureplenum chamber for splitting the air flow produced by said fan anddividing said chamher into two pressurized side-by-side cavities;

vertical stabilizer means mounted at the rear end of said body means fordeveloping a side force at the rear of said vehicle;

said air intake means and said vertical stabilizer means developing apair of side forces acting in substantially the same direction onopposite sides of the center of gravity of the vehicle when the vehicleis turned at an angle of yaw for maneuvering the vehicle in a shortturning radius while inhibiting spin of the vehicle about its center ofgravity.

3. The air cushion vehicle defined in claim 2 and wherein said centralcockpit means comprises an inner housing mounted Within said lightweight body in the path of the air flow from said fan having an openingfor the operator at the top of said body, the exterior configuration ofsaid housing in the path of said air flow being streamlined, saidstreamlined configuration including a pair of longitudinally disposedvertical sides respectively converging toward the front and rear ends ofsaid vehicle to provide a sharp,

vertical leading edge in the path of the air flow.

4. The air cushion vehicle described in claim 2 com-:

prising a rigid light-weight structural assembly comprising a bottomframework, an inner cockpit housing, and a diagonal support memberaflixed between the forward end of said bottom framework and the upperportion of the front end of said cockpit housing, said.

diagonal support member comprising in combination a cylindrical ring anda support bracket fastened be-.

tween the bottom and top of said ring, said cylindrical ring and saidsupport bracket being mounted in said air intake for both directing theair smoothly into said air intake and for supporting said motor-drivenfan.

5. The air cushion vehicle described in claim 2 wherein said airpressure chamber is formed by a framework of light weight tubing coveredwith a flexible mem- 8. The air cushion vehicle described in claim 6wherein said flexible membrane comprises plastic sheet material,

with reinforcing fibers for added strength. 9. The air cushion vehicledescribed in claim 2 comprising flaps forming a portion of the upperrear right and left surfaces of said body and having portions extendingproximate said vertical stabilizer for directing a flow of air from saidair pressure chamber toward the ver-. tical surface of said stabilizer.

10. An air cushion vehicle comprising a light-weight body providing. anair pressure chamber,

an air intake located in the forward end of said ve-;

hicle, a motor driven fan mounted in said air intake, a stabilizingvertical surface mounted at the rear end of said body, at least aportion of which is adapted to pivotal movement for controlling thedirection of travel of said vehicle,

means for propelling, braking, and controlling the direction of travelof said vehicle comprising only two movable flaps forming a portion ofthe upper rear 1 right and left surfaces of said body, said flaps beingpivotally mounted upon generally horiozntal axes; and

means for moving said flaps in both the same and respectively oppositedirections about their respective pivot axes to positions substantiallywithin said body, flush with the surface of said body and substantiallywithout said body.

11. An air cushion vehicle comprising an air pressure chamber,

an air intake,

means in said air intake for maintaining air'under pressure in said airpressure chamber,

means for propelling, braking and controlling the direction of travel ofsaid vehicle comprising only two movable flaps formed in the surface ofsaid body,

said flaps having a neutral position substantially flush with thesurface of said body, and

means for (l) applying force to said flaps for deflecting said flapsagainst the force exerted by the air pressure therewithin, and (2)releasing said force so that said flaps are deflected out of said bodyby the force exerted by the air pressure therewithin. 12. The aircushion vehicle described in claim 11 a plastic sheet ma-.

wherein said means for applying force to said flaps compnses a controlmember mounted for both rotational and translational movement about apredetermined axis so that rotational movement of said control memberdeflects said flaps differentially and translational movement of saidcontrol member deflects said flaps in the same direction.

13. In an air cushion vehicle having a body with a hollow under sideproviding an air pressure chamber, an air intake and means in said airintake for maintaining air under pressure in said air pressure chamber;

flaps forming a portion of the upper rear right and left surfaces ofsaid body, said flaps being pivotally mounted at their rear edges upongenerally horizontal transverse axes, each flap having a lowered controlposition wherein the flap is inside said body, a neutral positionwherein the flap is substantially flush with the surface of said body,and a raised, control portion wherein the fiap is substantially outsideof said body.

14. The air cushion vehicle defined in claim wherein each of said flapsis open at its outer end thereby permitting a side thrust component inthat direction when said flap is raised out of said body and beinggenerally closed at their inner end thereby preventing a thrustcomponent in the opposite transverse direction.

15. The air cushion vehicle defined in claim 14 wherein the inner endsof said flaps are closed by respective partial end plates at the innerends of said flaps.

16. An air cushion vehicle comprising an inner streamlined cockpithousing having a pair of sides extending outwardly at their mid portionand joined together at their respective ends to form respective acuteangles at the front and rear of said housing,

a light weight framework attached to said cockpit housing, saidframework extending out from the sides and the front of said housing,

a cylindrical ring afiixed between the forward end of said framework andthe upper front end of said cockpit housing whereby said ring issupported in a forwardly sloping position;

a thin, flexible shroud covering said framework with said ring beingleft open to form an air intake occupying substantially the entireforward end of said vehicle, said framework covered shroud forming anair pressure chamber having a downwardly, generally open underside forproviding an air pressure plenum chamber,

a motor driven fan mounted in a sloping position in said air intake formaintaining air under pressure within the air pressure chamber providedby said framework covered shroud, said streamlined housing beinglongitudinally disposed in said air pressure chamber in the path of theair flow produced by said motor driven fan, and

a vertical stabilizer mounted at the rear end of said body fordeveloping a side force at the rear of said vehicle, said stabilizercomprising a large vertical surface oriented generally parallel to thelength of the vehicle and extending away from said body, a portion ofsaid stabilizer being adapted for pivotal'movement for controlling thedirection of travel of said vehicle.

References Cited by the Examiner UNITED STATES PATENTS 2,828,929 4/1958Lippisch 24423 3,000,772 9/1961 Lunn 154-52.5 3,078,939 2/1963 Bollum1807 3,088,536 5/1963 Chezem 1807 3,130,939 4/1964 Alper et a1. 18073,140,687 7/1964 Beardsley 1807 3,150,731 9/1964 Franklin et al 18073,159,228 12/1964 Byrne et al 1807 3,180,443 4/1965 Jones 1807 3,194,3337/ 1965 Cockerell 1807 OTHER REFERENCES Design News, May 23, 1960,Ground Cushion Vehicle Balances With Single Engine, V. W. Wigotsky, p.607.

Aviation Week, July 6, 1959, Curtiss-Wright Tests Air Car Prototype, E.J. Bulban, pp. 115116.

BENJAMIN HERSH, Primary Examiner.

A. HARRY LEVY, Examiner.

M. S. SALES, Assistant Examiner.

2. AN AIR CUSHION VEHICLE COMPRISING LIGHTWEIGHT BODY MEANS HAVING AHOLLOW, DOWNWARDLY GENERALLY OPEN UNDERSIDE FOR PROVIDING AN AIRPRESSURE PLENUM CHAMBER; AIR INTAKE MEANS INCLUDING AN INTAKE AND FAN INTHE FORWARD END OF SAID PLENUM CHAMBER FOR (I) VERTICALLY LIFTING SAIDVEHICLE, (II) PROVIDING A HORIZONTAL THRUST SUBSTANTIALLY PARALLEL TOTHE LONGITUDINAL AXIS OF SAID VEHICLE, AND (III) PROVIDING A SIDE FORCECOMPONENT AT THE FRONT OF THE VEHICLE WHEN SAID VEHICLE IS FLYING AT ANANGLE OF YAW; CENTRAL COCKPIT MEANS EXTENDING LONGITUDINALLY WITHIN SAIDAIR PRESSURE PLENUM CHAMBER FOR SPLITTING THE AIR FLOW PRODUCED BY SAIDFAN AND DIVIDING SAID CHAMBER INTO TWO PRESSURIZED SIDE-BY-SIE CAVITIES;VERTICAL STABILIZER MEANS MOUNTED AT THE REAR END OF SAID BODY MEANS FORDEVELOPING A SIDE FORCE AT THE REAR OF SAID VEHICLE; SAID AIR INTAKEMEANS AND SAID VERTICAL STABILIZER MEANS DEVELOPING A PAIR OF SIDEFORCES ACTING IN SUBSTANTIALLY THE SAME DIRECTION ON OPPOSITE SIDES OFTHE CENTER OF GRAVITY OF THE VEHICLE WHEN THE VEHICLE IS TURNED AT ANANGLE OF YAW FOR MANEUVERING THE VEHICLE IN A SHORT TURNING RADIUS WHILEINHIBITING SPIN OF THE VEHICLE ABOUT ITS CENTER OF GRAVITY.